The number of signatures we have, is usually not important; the most dangerous viruses are normally the current crop, not ones that are 5 years old and are most likely not even in circulation any more.

The point I was trying to get across was if the AV companies thought along the same lines as what you stated. There has to be a starting point for all sigs, was just wondering how far back the current version of NOD32 goes.

NOD32's core development team has been with us from the very start, and
we believe they are the most talented and highly skilled group of virus
researchers and antivirus programmers in the world today. They have
consistently maintained the unsurpassed quality of the NOD32 Antivirus
System since its release in May 1988 (before the creation of Eset as a company)....